JP5255132B2 - Multi-tone character display method, multi-tone character display device, multi-tone character display program, television receiver equipped with multi-tone character display device, and mobile phone equipped with multi-tone character display device machine - Google Patents

Description

  The present invention relates to a character display method, a character display device, a character display program, and the like that can be optimally applied when displaying characters on an OSD (on-screen display) in a display device of various information devices typified by a television receiver. More specifically, a multi-gradation character display method that can be optimally applied when one or more gradations having different levels are added to the outline of the character font of the OSD-displayed character and displayed as a multi-gradation character, The present invention relates to a display device, a character display program, a television receiver including the display device, and the like.

  Currently, television receivers and the like are equipped with a function for displaying characters on an OSD (on-screen display), and are used to display various character information. The television receiver is usually used as a worldwide television receiver with the same hardware configuration, although the language used differs depending on the country of use, but other hardware configurations are common. .

  This worldwide television receiver incorporates a large number of characters (character fonts) corresponding to a large number of languages in order to support OSD display in different languages. (Letter) can be selected.

  In such a world-wide television receiver, when the language is switched and OSD display is performed, the number of characters of the translated word may vary greatly depending on each language.

  FIG. 12 shows such a case. For example, when the character “Hello” in English shown in FIG. 12A is displayed in the display area 521 of a predetermined space on the display screen 520, the language used is switched to German display. Think about what to do.

  If you translate the word “Hello” into German “Guten Morgen” and display it in the predetermined display area 521, you will see a significant change from 5 English characters to 12 German characters (including one space). This increases the number of characters and may exceed the predetermined character frame of the display area 521. FIG. 12B shows a case where the character frame of the display area 521 determined in advance is exceeded.

  On the other hand, on the OSD display screen, it may be required to display a translated word in a predetermined display area 521 due to a request on the screen design. In such a case, it is necessary to adjust the character string to be displayed within the predetermined display area 521 by narrowing the character spacing and the like. FIG. 12C shows a situation in which the character string “Guten Morgen” is accommodated in the predetermined display area 521 by adjusting the character spacing.

  In addition, when alphanumeric characters are expanded at equal intervals with the same font size, the character spacing may be too large, especially in alphanumeric characters, the balance of the entire character string may be deteriorated, and the display may be uncomfortable. . This is particularly noticeable when displaying a mixture of Japanese and alphanumeric characters.

  Patent Document 1 discloses a technique for displaying characters uniformly by appropriately setting the character spacing when various characters are displayed in a bitmap memory type character display control device.

  FIG. 13 is a block diagram illustrating a configuration of a character display control device for appropriately setting the character spacing described in Patent Document 1. In FIG. 13, when a character code is input from the CPU 501, the character code determination circuit 506 determines the character code and determines whether or not the character is better to adjust the character spacing. The character width determination circuit 508 generates character width information for the accessed character pattern for one character from the character pattern memory 503 based on the determination result of the character code determination circuit 506. The arithmetic circuit 510 appropriately adjusts the character spacing in the horizontal direction of the character pattern for one character based on the character width information.

  Specifically, when the alphabet “I” is displayed on the display screen of the display device, the number of dots in the horizontal direction of the font itself is, for example, 3 dots, and the number of dots in the entire character pattern (for example, 8 dots). When displayed as a character string, there are cases where it is difficult to see because there are too many character spaces. According to the technique disclosed in Patent Document 1, the character spacing can be adjusted to an appropriate value for such characters.

  In addition, recently, when OSD displaying a character, one or more gradations (hereinafter simply referred to as “one or more gradations”) having different brightness levels (or luminances) on the outline of the character font. In some cases, high-quality characters with smoothed edges and character curves are used.

  FIG. 14 shows an example of a multi-gradation character in which two gradations (gradation 1 and gradation 2) are added to the outline of the character font. In the upper half portion of FIG. 14, two gradations (gradation 1 and gradation 2) are added to the outline of the character font of the character “e”, and a multi-gradation character (hereinafter referred to as “multi-level character”). In the lower half of FIG. 14, a multi-tone character font portion 530 (hereinafter also simply referred to as “character font 530”) is shown. The gradation 1 portion 531 (hereinafter also simply referred to as “gradation 1 portion 531”), the gradation 2 portion 532 (hereinafter also simply referred to as “gradation 2 portion 532”), and the background portion 533. Each gradation (hereinafter also referred to as “brightness (luminance) level” in the present specification) is represented by a simple graph.

  Referring to the upper half of FIG. 14, a multi-gradation character is shown in which a gradation 1 portion 531 and a gradation 2 portion 532 are added to the periphery (outline) portion of the original character font 530 of the character “e”. You can see that In the lower part of FIG. 14, the gradation (brightness (luminance) level) of the character font 530, the gradation 1 portion 531, the gradation 2 portion 532, and the background portion 533 is shown by a simple graph. Yes.

  Although it can be read from the graph showing the gradation (brightness level), in the example shown in FIG. 14, the brightness (brightness) level of the character font 530 and the brightness (brightness) of the background portion 533 are shown. A gradation 1 portion 531 and a gradation 2 portion 532 having brightness (luminance) divided substantially equally are added between the levels. In FIG. 14, the width of the line constituting the character font 531 (the thickness of the character line), the width of the gradation 1 portion 532, and the width of the gradation 2 portion 533 are shown to be not so different. The width of a plurality of gradations to be added may be made relatively narrower than the line width of the character font 531. The graph shown in the lower part of FIG. 14 shows the level of brightness (luminance) measured along the line segment A-A ′ shown in the upper part of FIG. 14.

JP-A-5-241557 (published on September 21, 1993)

  In order to display text with the same content in the same frame in consideration of the design of the display screen, even when the language used is changed, in a worldwide television receiver capable of OSD display in multiple languages It is necessary to take a technique such as (1) displaying with reduced character spacing, (2) displaying with a reduced character size, and (3) scrolling and displaying the corresponding character when selected.

  If the length of the sentence (number of characters) does not differ so much when the language is switched, any method can be used to fit within the predetermined display area, but the display after applying the method In either case, the visibility may deteriorate. In addition, in the case of scroll display, even if the sentence after language switching becomes long, it can be displayed, but it takes time to recognize the whole sentence, and since the character itself scrolls, After all visibility becomes worse.

  Display with the character spacing reduced or narrowed is less likely to degrade visibility when the number of characters does not increase that much. However, when high-quality character display is performed using the multi-gradation characters described with reference to FIG. 14, if the character spacing is narrowed, the visibility may be significantly reduced.

  FIG. 15 is a diagram showing how the visibility changes when the character spacing is narrowed when multi-tone characters are used. FIG. 15 includes five diagrams of FIG. 15A to FIG. 15E, and each diagram is further divided into three parts: an upper part, an intermediate part, and a lower part. In the upper part of FIGS. 15A to 15E, the display state of the character string “ABCD” when stored in different spaces (indicated by the pixel width) is shown. In the character string “ABCD”, a more detailed display state focusing on the outline portion of the adjacent character is shown. In the lower part, the display state of the adjacent characters shown in the intermediate part is shown in the brightness (luminance) level.

  In FIG. 15, for convenience of explanation, a character with one “gradation 1” added to the outline of the character font is shown as an example. That is, for the background portion 542, the character font 540 and the gradation 1 portion 541 added to the outline of the character font are shown. In FIG. 15, 543 indicates the brightness level of the character font 540, 544 indicates the brightness level in the gradation 1 portion 541, and 545 indicates the brightness level in the background portion 542. .

  As shown in FIG. 15A, when the character string “ABCD” is stored in a sufficiently wide space (width) and displayed, there is a sufficiently wide space 546 between the characters of the character string “ABCD”. When the character string “ABCD” is accommodated in a space of about 90 pixels (see FIG. 15B), the interval between the two characters becomes an interval 547 that is slightly narrower than the interval 546. However, in any case, there is a considerably wide background portion 542 between the characters, and the visibility is not so bad.

  When the character string “ABCD” is stored in a narrower space, for example, a space of about 80 pixels (see FIG. 15C), a narrower space 547 ′ is formed between the two characters, and the background portion is between the characters. Although 542 is left, the visibility when the character string “ABCD” is viewed from a distant place, for example, is deteriorated. When the character string “ABCD” is further reduced to a space of about 70 pixels, for example (see FIG. 15D), the gradation 1 portion 541 of each adjacent character is in direct contact, and the character and the character The background portion 542 is not left in between. As a result, the character string “ABCD” cannot be sufficiently contrasted, and the visibility is considerably deteriorated.

  As shown in FIG. 15E, when the character string “ABCD” is accommodated in a narrower space, the character fonts 540 of the adjacent characters become very closely spaced 548 ′, and the brightness of the character font 540 is between them. As a result, only the gradation 1 portion 541 having a brightness very close to is sandwiched. As a result, the contrast between adjacent characters is lowered, and the visibility of the character string “ABCD” is extremely deteriorated.

  As described above, when one or more gradations are added to the outline of a character font and a character string in which input character data is displayed as a multi-gradation character is displayed in a narrower space, the character visibility is reduced. Has the problem of becoming worse.

  According to the technique disclosed in Cited Document 1, even if the character string includes a mixture of characters with short dimensions in the width direction, the character spacing can be adjusted to an appropriate value for such characters. In some cases, the width of the entire character string can be reduced accordingly. However, one or more gradations are added to the outline of the character font to display the input character data as multi-gradation characters. No consideration has been given to the characters that have been made, and the above-described problem cannot be solved by the technique described in Cited Document 1.

  The present invention has been made in view of the above-mentioned problems of the prior art, and a character string composed of multi-gradation characters obtained by adding one or more gradations to the outline of a character font is stored in a narrower space. It is another object of the present invention to provide a multi-tone character display method, a display device, and the like that can be displayed as multi-tone characters as much as possible while minimizing degradation of visibility.

In order to solve the above problem, in the multi-tone display method according to the present invention,
A multi-gradation character display method in which one or more gradations are added to the outline of a character font so that input character data can be displayed as multi-gradation characters.
A multi-gradation character creation step for creating a multi-gradation character by adding one or more gradations to the outline of the character font of the input character data;
A gradation difference measuring step for measuring a gradation difference between a gradation of the character font portion of the multi-gradation character and a gradation in an intermediate portion between adjacent multi-gradation characters;
And correcting the gradation of the multi-gradation character based on the gradation difference obtained in the step of measuring the gradation difference to create a corrected multi-gradation character,
Based on the gradation difference obtained in the step of measuring the gradation difference, the corrected multi-gradation character is output instead of the output of the character to which no gradation is added.

  According to this, when a predetermined character string is displayed in a predetermined space, a multi-gradation character with high display quality is automatically displayed in accordance with the space to be displayed with a minimal deterioration in visibility. It is possible to display. In addition, when the display space is extremely small, it is possible to automatically reduce all gradations of a multi-gradation character and perform display while preventing deterioration of visibility. This is particularly effective when displaying characters with a small difference in brightness between the character font color (character color) and the character background color (background color), and when the character spacing is narrow. Visibility degradation can be suppressed.

In order to solve the above problem, in another multi-tone display method according to the present invention,
The gradation difference measuring step includes a step of measuring a character interval between adjacent characters and a step of converting to a gradation difference based on the character interval.

  According to this, the gradation difference can be accurately obtained without measuring the actual brightness level in the character font portion of the multi-gradation character and the intermediate portion between the multi-gradation characters, and the gradation difference is measured. There is no need for special hardware. That is, if the gradation level and width to be added to the outline of the character font are registered in advance, the gradation difference can be calculated by measuring the character spacing.

In order to solve the above problem, in another multi-tone display method according to the present invention,
The step of creating the corrected multi-gradation character includes the step of adding the added gradation when the gradation difference measured in the gradation difference measurement step is smaller than a predetermined first gradation difference. It is a step that removes everything.

  According to this, it is possible to display multi-gradation characters according to the space to be displayed by a relatively simple process, and it is possible to easily mount it on a portable device or the like where it is difficult to load a high-speed CPU. .

In order to solve the above problem, in another multi-tone display method according to the present invention,
The step of creating the corrected multi-tone character includes
If the gradation difference measured in the gradation difference measurement step is smaller than a predetermined first gradation difference, removing all the added gradations;
A second gradation difference measured in the gradation difference measurement step is greater than the first gradation difference, and is a predetermined gradation difference that is greater than the first gradation difference. When the gradation difference is smaller than the gradation difference, a step of removing the added gradation until the second gradation difference is reached, and multi-gradation characters greater than or equal to the second gradation difference are output. It is characterized by doing.

  According to this, the multi-gradation character that is output and displayed becomes a multi-gradation character having at least a gradation greater than or equal to the second gradation difference, and has the effect of ensuring the visibility of the designed value.

In order to solve the above problem, in another multi-tone display method according to the present invention,
The step of creating the corrected multi-tone character includes
When the gradation difference measured in the gradation difference measurement step is a gradation difference larger than the first gradation difference and smaller than the second gradation difference, it is farthest from the character font part. It is characterized by removing the added gradation.

  According to this, there is an effect that a minimum visibility can be secured by a relatively simple process.

In order to solve the above problem, in another multi-tone display method according to the present invention,
The one or more gradations added to the outline of the character font by the multi-gradation character creation step are gradations obtained by equally dividing the difference between the gradation of the character font part and the gradation of the background part of the character. It is characterized by being.

  According to this, there is an effect that the gradation difference can be easily obtained by measuring the space between characters.

In order to solve the above problem, in another multi-tone display method according to the present invention,
One or more gradations added to the outline of the character font of the input character data reduce the gradation change closer to the character font part and increase the gradation change closer to the character background part. It is characterized by that.

  According to this, it is possible to greatly improve visibility by removing only the gradation added to the outermost side of the character font in multi-gradation characters, and it is possible to greatly improve visibility even with relatively simple processing. The effect that can be improved. That is, with this configuration, the separation between characters increases, so that the visibility is improved.

In order to solve the above problem, in another multi-tone display method according to the present invention,
A character font portion of the multi-tone character is white, and a background portion of the character is black.

  According to this, there is an effect that it is possible to display a multi-tone character with good contrast on a dark background portion.

In order to solve the above problem, in another multi-tone display method according to the present invention,
A character font portion of the multi-tone character is black, and a background portion of the character is white.

  According to this, there is an effect that it is possible to display a multi-tone character with good contrast on a dark background portion.

In order to solve the above problem, in the multi-tone character display device according to the present invention,
A character gradation generation unit that generates a multi-gradation character by adding one or more gradations to the outline of the character font, and multi-gradation with one or more gradations added to the outline of the character font. A character display device that can be displayed as characters,
A gradation difference measurement unit for measuring a gradation difference between a gradation of a character font part of a multi-gradation character and a gradation in an intermediate portion between adjacent multi-gradation characters;
A switching unit for switching and outputting the character output without gradation added and the multi-gradation character generated by the character gradation generation unit based on the measurement result of the gradation difference measuring unit; It is a feature.

  According to this multi-gradation character display device, when the “gradation difference measured in the gradation difference measurement step is smaller than the first gradation difference determined in advance”, The step of removing all of the keys can be realized very easily.

In order to solve the above problem, in the multi-tone character display device according to the present invention,
Character display that includes a character gradation generation unit that adds one or more gradations to the outline of a character font, and that can display input character data as multi-gradation characters with one or more gradations added to the outline of a character font A device,
A gradation difference measurement unit for measuring a gradation difference between a gradation of a character font part of a multi-gradation character and a gradation in an intermediate portion between adjacent multi-gradation characters;
A correction multi-tone character generation unit that corrects the tone of the multi-tone character generated by the multi-tone character generation unit to create a correction multi-tone character,
Based on the measurement result of the gradation difference measuring unit, it is possible to switch between the character output without gradation and the corrected multi-gradation character.

  According to this, when a predetermined character string is displayed in a predetermined space, a multi-gradation character with high display quality is automatically displayed in accordance with the space to be displayed with a minimal deterioration in visibility. A display device capable of displaying can be provided. In addition, when the display space is extremely small, it is possible to provide a display device that can automatically reduce all the gradations of a multi-gradation character and prevent display deterioration.

  In order to solve the above problems, a television receiver according to the invention of the present application is provided with the display device for multi-gradation characters, and the portable device according to the invention of the application has the multi-gradation. It is equipped with a character display.

  According to this, it is possible to provide a television receiver or a portable device that can perform high-quality character display using multi-gradation characters while minimizing visibility degradation.

  In order to solve the above problems, the program according to the invention of the present application is capable of operating each unit included in the multi-tone character display device according to the invention of the present application as realizing the functions of each unit. It is said. Therefore, by using this program, a television receiver and a portable device to which the multi-tone character display method of the present application is applied can be realized.

  In order to solve the above problems, the recording medium according to the present invention is a recording medium in which a computer program capable of operating the multi-tone character display device according to the present invention is recorded. Yes. According to this, the computer program which can implement | achieve the display method of the multi-tone character of this application can be easily distributed or provided.

  As described above, according to the invention of the present application, when high-quality character display using multi-gradation characters is performed in a predetermined space, the space between characters is reduced due to reasons such as a narrow display space. Even if it gets narrower, while maintaining a certain level of display quality. Multi-tone character display can be performed while maintaining necessary visibility.

It is a flowchart which shows the display method of the multi-tone character which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the display state when a multi-tone character provided with one or more gradations in an outline is stored in a narrower space, and the display state after applying the present invention. It is a figure which shows an example of the display apparatus which can apply the display method which concerns on Embodiment 1 of this invention. It is a figure which shows an example of a multi-tone character. It is a figure for demonstrating an example of the display state of a multi-tone character at the time of applying Embodiment 1 of this invention. It is a figure for demonstrating the other example of the display state of a multi-tone character at the time of applying Embodiment 1 of this invention. It is a figure which shows the example of the multi-tone character which is a multi-tone character which can apply this invention, and the difference of the level of a gradation differs for every gradation. It is a figure which shows the display method of the multi-tone character which concerns on Embodiment 2 of this invention. It is a figure which shows the state of a multi-tone character display at the time of applying Embodiment 2 of this invention. It is a figure which shows an example of the display apparatus which can apply the display method which concerns on Embodiment 2 of this invention. It is a figure which has an OSD process part and shows an example of the circuit structure of the television receiver which can apply this invention. It is a figure explaining the case where the text of a different number of characters is displayed on the decided area | region. It is a figure which shows the conventional character control method which adjusts and displays the character space | interval between fonts for every font. It is a figure which shows the structural example of a multi-tone character. It is a figure which shows the state of a display when the display space | interval of a multi-tone character is narrowed.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, various preferred limitations for implementing the present invention are given, but the technical scope of the present invention is not limited to the description of the following examples and drawings.

Embodiment
Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same reference numerals are assigned to the same members and the like, and thus detailed description of those members and the like is omitted.

<Embodiment 1>
A first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a flowchart showing a multi-tone character display method according to Embodiment 1 of the present invention. FIG. 2 shows multi-tone character display according to the present application when multi-tone characters are displayed. It is a figure for demonstrating the outline | summary at the time of applying a method.

  First, the outline of the multi-tone character display method according to the present invention will be described with reference to FIG. 2 (a), (b), and (c), the upper part shows the display state of the character string “little” configured as a multi-tone character, and the lower part shows the multi-tone character A graph showing the display status of the character string “little” configured as a gradation (brightness level) is shown.

  2 shows an example of a multi-gradation character in which two gradations are given to the outline of each character font of the character string “liter”. FIG. 2A shows a case where the character spacing is not shortened. A display example is shown, and FIG. 2B shows a display example when the display interval of the character string “little” is narrowed. FIG. 2 (c) shows a display example in which when the character visibility becomes worse as a result of narrowing the character spacing, the character display method is changed according to the present invention to improve the visibility of the displayed characters. Show.

  Note that the case where the display interval of the character string to be displayed is narrow is, for example, the case described with reference to FIG. 12, and therefore, in a worldwide television receiver or the like, there are many cases. It is understood that it is extremely effective to apply the multi-tone character display method of the present application described below when switching the language display.

  However, the present invention is not limited to such a case. For example, in a television receiver, when performing PIP (Picture in Picture) display in which other channels are displayed on a sub-screen, a predetermined character string is displayed on a small screen without breaking the design of the sub-screen. The present invention can be effectively applied to display.

In the graphs shown at the bottom of FIGS. 2A, 2 </ b> B, and 2 </ b> C, reference numeral 210 denotes a gradation (brightness level) of a character font portion (hereinafter simply referred to as “character font”) 200. , 211 indicates the added gradation 1 portion (hereinafter simply referred to as “gradation 1 portion”) 201 (brightness level), and 212 indicates the added A gradation 2 portion (hereinafter simply referred to as “gradation 2 portion”) 202 indicates a gradation (brightness level), and 213 indicates a gradation (brightness (or luminance) of the background portion 203. Level). (As described above, instead of describing “gradation of character font 200” or the like, “brightness (or luminance) level of character font 200” or simply “brightness of character font 200” will be described hereinafter. Also described as “Level of”.)
As shown in FIG. 2A, when the character string “liter” is displayed in a normal state, that is, with a sufficient interval (that is, when a background portion 203 having a sufficient width exists between them) For example, two gradations (gradation 1 part 201 slightly darker than the brightness of the character font part and gradation 2 part 202 darker than gradation 1 but brighter than the background part) are added to the outline of the character font. However, the multi-gradation portions added to the outline are separated from each other, and the background portion 203 exists, and there is no problem in the visibility of the characters. On the contrary, by giving gradation to the outline of the character font, a high quality character display without a jagged feeling that is likely to occur in a bent part of the character is performed.

  FIG. 2B shows a display state when the length of the character string has to be shortened for some reason, for example, the situation described with reference to FIG. As shown in FIG. 2B, when the character string is composed of multi-gradation characters, the interval between adjacent characters becomes extremely narrow depending on the degree of shortening of the character string, and the character font has an outline portion. The provided gradation 2 portion 202 may not be displayed. In this case, only the gradation 1 portion 201 is barely left between the two characters.

  In this case, as is apparent from the graph shown in the lower part of FIG. 2B, only the gradation 1 portion (brightness 211 portion) exists between the two multi-gradation characters. The entire character string is displayed with low contrast and poor visibility.

  Therefore, in the case where the difference in gradation is such that visibility is deteriorated, the gradation added to the character font 200 is corrected. FIG. 2C shows an example in which the gradation 1 portion 201 and the gradation 2 portion 201 are deleted as an example of correcting the gradation. In this case, as a result, the entire gradation portion is deleted, and the display quality of the characters is somewhat deteriorated, but the display is excellent in visibility. In the present invention, “gradation difference” is synonymous with a difference in brightness (or luminance) between two gradations having different brightness, for example, “gradation 1 portion 201” and “gradation 2 portion 202”. The meaning is used.

  In the example shown in FIG. 2, the gradation difference between the gradation (brightness) of the character font 200 and the gradation (brightness) in the intermediate portion between adjacent multi-gradation characters is measured, and as a result of the measurement, When the gradation difference is such that the visibility deteriorates, the gradation of the multi-tone character is corrected and the corrected multi-tone character (corrected multi-tone character) is displayed. . In this case, by appropriately selecting the degree of correction, for example, as shown in FIG. 2C, by removing all assigned gradations, the brightness of the background level can be reduced between displayed characters. It is also possible to sandwich the portion, and display with good visibility can be performed. Other modes for correcting the gradation of multi-gradation characters will be described more specifically with reference to FIGS.

  With reference to FIG. 1 and FIG. 3, an example of a flow for realizing the display described in FIG. 2 and a multi-tone character display device that can implement the flow will be described. FIG. 1 is a flowchart for explaining the embodiment 1 according to the multi-tone character display method of the present invention, and FIG. 3 is an example of a multi-tone character display device capable of carrying out such a flow. It is.

  FIG. 3 shows a display device to which the multi-tone display method according to the present invention can be applied by connecting to an OSD display device such as a television receiver. In FIG. 3, 101 is an OSD generation unit that performs OSD display of the television receiver, as described above, and the OSD generation unit 101 displays, for example, program information, information on the operation of the television receiver, and the like on-screen.

  Although not explicitly shown in FIG. 3, the character gradation generation unit 103, the gradation difference measurement unit 104, the character gradation correction unit 105, which will be described below, including the OSD generation unit 101 shown in FIG. The switching unit 106 is controlled by a CPU provided in the television receiver main body or the like.

  In FIG. 3, the character string data to be OSD displayed from the OSD generation unit 101 is first stored in the buffer memory 102. The flow diagram of FIG. 1 is a multi-tone character that receives character string data stored in the buffer memory 102 of FIG. 3, converts the character string data into multi-tone characters, and displays them in a predetermined area. Shows the display method.

  In FIG. 1, when character string data to be displayed is received from the buffer memory 101, the character gradation generation unit 103 adds one or more gradations to the outline of the character font to create a multi-gradation character (step). 1). Since the data from the OSD generation unit 101 is normally displayed in a predetermined display area, it is determined whether or not a multi-gradation character with one or more gradations can be accommodated in the display area. Confirm (step 2). This confirmation operation can be performed using a CPU for controlling a display device not shown in FIG. 3 or using a CPU of a television receiver, for example, as already described.

  When the character string of the multi-tone character does not fit in the predetermined display area, the character interval (pitch) is further reduced (step 3), and the character string of the multi-tone character is further displayed in the predetermined display area. It is confirmed whether it fits (step 4), and the operation of reducing the character spacing and the confirmation operation are repeated until the character string of multi-gradation characters fits in a predetermined display area.

  After confirming that the character string of the multi-tone character is within the predetermined area, the tone difference measuring unit 104 determines the tone level of the character font 200 and the intermediate level between adjacent multi-tone characters. The gradation difference from the tone is measured (step 5). For example, in FIG. 2B, the gradation in the middle portion between two adjacent multi-gradation characters is the gradation of the portion indicated by 221. In the case of FIG. “Tone 1”. Then, as indicated by a circle 222 in FIG. 2B, the gradation difference is determined by the brightness (or luminance) level 210 of the character font 200 and the brightness (or brightness) of the added gradation 1 portion 201 (or (Luminance) level 211.

  The gradation difference is measured by, for example, storing the gradation 1, gradation 2, and the brightness of the background portion together with the brightness of the character font portion 200, and reducing the character spacing and developing the characters in the memory. From the above, the gradation difference can be calculated.

  FIG. 1B describes another measurement method for measuring the gradation difference. The method for measuring the gradation difference is as follows. That is, normally, when adding gradation to the outline of a character font, the brightness level of each gradation to be added and the width (pitch) of the gradation to be added are determined in advance. ), By determining the character interval (pitch), the character interval (pitch) is calculated by dividing the character interval (pitch) between “the gradation of the character font 200” and “the gradation in the intermediate portion between adjacent multi-gradation characters”. Can be converted to gradation difference.

  Based on the gradation difference obtained by the measurement, the character gradation correction unit 105 corrects the gradation of the multi-gradation character generated by the character gradation generation unit 103 and creates a corrected multi-gradation character. Will do.

  FIG. 1 shows an example of a correction method for correcting the gradation of a multi-tone character. For example, assuming that there are N gradations in total from the brightness of the character font part (gradation 0) to the brightness of the background part (gradation N), the gradation obtained in step 5 above. It is determined whether or not the difference is 50% or more of the N gradations (step 6). If the difference is not 50% or more, all gradations are removed (step 8). That is, the gradation difference corresponding to 50% is set as the first gradation difference, and if it is not greater than the first gradation difference, all assigned gradations are removed.

  Even if the gradation difference is 50% or more, it is checked whether or not the gradation difference is 80% or more (step 7). The nth gradation, which is the gradation farthest from the gradation of the font part, is removed (step 9). Then, the gradation difference is measured again (step 6), it is confirmed that the gradation difference is 80% or more (step 7), and the gradation correction process is terminated. That is, a gradation difference corresponding to the gradation difference of 80% is set as the second gradation difference, and after confirming that the gradation difference is equal to or greater than the second gradation difference, the process is terminated.

  In step 2, if the created multi-gradation character is in the display area, the process is naturally terminated without performing gradation correction. The gradation difference that determines whether or not the gradation is corrected is not limited to 80%, and may be, for example, 75%. When this ratio is lowered, the effect of improving the visibility is somewhat reduced, but instead, the ratio at which multi-gradation characters that are high-quality characters are displayed as they are is increased.

  In step 7, when less than 80%, the gradation is removed until the gradation difference becomes 80% or more, but a simpler method can be adopted.

  Such an example is shown in FIG. In this case, it is determined in step 7 based on whether or not the gradation difference is 70% or more. If the gradation difference is 70% or more, the display is allowed as it is. If it is less than 70%, the nth gradation is removed, that is, the outermost gradation part is removed from the plurality of gradations added to the character font. Even in the case of this display method, although it is a simple process, a gradation difference of 50% or more is secured at least, and appropriate visibility can be secured.

  As described above, from step 5 to step 9 or from step 5 to step 9 ′, the gradation of the character font portion of the multi-tone character and the gradation at the intermediate portion between the adjacent multi-tone characters A step of measuring a gradation difference and a step of correcting a gradation of a multi-gradation character to create a corrected multi-gradation character based on the gradation difference obtained by the step of measuring the gradation difference are configured. You can see that

  Hereinafter, a method of creating a corrected multi-tone character by correcting the tone of the multi-tone character more specifically will be described with reference to FIGS. 4, 5, and 6.

  FIG. 4 shows a state in which the multi-tone character 305 and the multi-tone character 315 are adjacent to each other but are displayed at sufficiently spaced intervals that do not deteriorate the visibility. The multi-gradation character 305 has three gradations, a gradation 1 portion 301, a gradation 2 portion 302, and a gradation 3 portion 303 added to the character font 300. , A gradation 1 portion 311 added adjacent to the character font 310, a gradation 2 portion 312, and a gradation 3 portion 313. In FIG. 4, for convenience of explanation, different numbers are assigned to the three gradations added to the multi-gradation character 305 and the multi-gradation character 315, but these are shown in the graph shown at the bottom of FIG. As shown, the brightness levels of the corresponding gradations are the same.

  The gradation 1, gradation 2, and gradation 3 added to the character fonts 300 and 310 of the multi-gradation characters 305 and 315 each have a width of 2 pixels. The portion 303 and the gradation 3 portion 313 of the multi-gradation character 315 are displayed as being separated by at least two pixels. Therefore, the character font 300 of the multi-tone character 305 and the character font 310 of the multi-tone character 315 are separated by 16 pixels or more. In such a case, the two characters are displayed with sufficient contrast, and there is no problem in visibility in normal display.

  As described above, in the case of the multi-tone characters 305 and 315 shown in FIG. 4, the multi-tone characters 305 and 315 have the same tone difference (brightness) in the tone 1, tone 2 and tone 3 respectively. Furthermore, the background portion 304 and the character font portions 300 and 310 are configured to have uniform gradation differences (brightness differences).

  FIG. 5A shows a state in which the display interval of the two multi-gradation characters 305 and 315 shown in FIG. 4 is narrowed. A state in which the portion 313 of gradation 3 of the gradation character 315 overlaps is shown.

  As described above, the gradation 1, gradation 2, and gradation 3 have the same gradation difference (brightness level difference) between the character font portions 300 and 310 and the background portion 304. Therefore, the gradation difference 350 in this case is 75% of the gradation difference between the background portion 304 and the character font portions 300 and 310. Note that the gradation difference 350 is a gradation difference (brightness) between a gradation (brightness) in the character font 300 portion of a multi-gradation character and a gradation (brightness) in an intermediate portion between adjacent multi-gradation characters. It can be seen that this is a difference in brightness. In Step 5 of FIG. 1, “measuring the gradation difference” means measuring the gradation difference 350.

  According to the display method of the first embodiment of the present invention shown in FIG. 1A, the gradation difference is determined to be 50% or more in Step 6, but it is not 80% or more in Step 7, so the third The gradation 3 is removed, and the gradation difference at that time is measured in step 5. Naturally, since the gradation difference is 100%, this is confirmed in step 7 and the processing is ended. FIG. 5B shows the situation at this time.

  In the example shown in FIG. 4, the corrected multi-tone character shown in FIG. 5B is created even in the modification shown in FIG.

  As a result, the multi-tone characters 305 and 315 are displayed as corrected multi-tone characters corrected as multi-tone characters 305 ′ and 315 ′ having two tones 1 and 2. In this case, since the gradation of the multi-tone character is reduced by one, the character quality of the display is slightly deteriorated, but the visibility is hardly deteriorated, so that the display quality as a whole is substantially deteriorated. The character spacing can be reduced without causing the

  FIG. 6 shows the “step of correcting the gradation of the multi-gradation character to create a corrected multi-gradation character” when the interval between the multi-gradation characters 305 and 315 is further narrower than in the case of FIG. The situation is shown. FIG. 6 shows a case where the interval between the multi-tone characters 305 and 315 shown in FIG. 4 is further narrower than in the case of FIG. Shows the case.

  In this case, the gradation difference measured in step 5 in FIG. 1 corresponds to 351 in FIG. In this case, the gradation difference is 50% and does not exceed 50%. Therefore, as shown in FIG. 6B, all gradations are removed. As a result, the multi-tone characters 305 and 315 are displayed only with the character fonts 300 and 310, respectively. Although the display quality of the characters cannot be improved due to the multi-gradation characters, the visibility of the display can be secured, and the minimum requirement for character display can be satisfied.

  In the above description, the brightness of each of the plurality of gradations 1, 2, and 3 added to the character font has been described as changing by the same brightness (luminance). The change in the brightness of the gradation to be applied is not limited thereto, and can be freely set according to preference and according to the purpose of use of the characters. For example, if you want to accurately convey the information to be displayed, set it so that the visibility can be improved. If the appearance (design) is more important than the accuracy of the content to be conveyed, the visibility is somewhat sacrificed. To improve the quality of the displayed characters.

  FIG. 7 shows an example in which, in the added gradation, the brightness change of the gradation on the side closer to the character font increases as the distance from the character font increases. That is, as shown in FIG. 7, the difference between the brightness of the character font 300 and the brightness of the gradation 1 portion 301 is set as a difference 371, and the difference between the brightness of the gradation 1 portion 301 and the gradation 2 portion 302 is set as a difference 372. When the difference between the gradation 2 portion 302 and the gradation 3 portion 303 is the difference 373, and the brightness difference between the gradation 3 portion 303 and the background portion 304 is the difference 374, the difference 371 <difference 372 <difference 373 < Configured as a difference 374. For example, the gradation difference may be changed logarithmically.

  It is said that the human sense is generally converted to logarithm, and therefore, the multi-gradation character with such gradation added is expected to be felt more smoothly by many people. In addition, it is expected that the configuration in which the added gradation is reduced does not give a sense of incongruity to more people. In this case, even if only the gradation 3 is removed, the contrast with the background portion is increased, and the effect of increasing the visibility is great.

<Embodiment 2>
A second embodiment of the present invention is shown in FIGS. Hereinafter, a multi-tone display method according to the second embodiment will be described with reference to FIGS.

  As shown in FIG. 8, the multi-tone character display method according to the second embodiment has basically the same configuration as the multi-tone character display method according to the first embodiment described with reference to FIG. However, the configuration is slightly different in the step of creating the corrected multi-tone character by correcting the tone of the multi-tone character. In FIG. 8, the same measurement method as described with reference to FIG. 1B is described as a method of measuring the gradation difference.

  Therefore, since steps 1 to 6 in FIG. 8 have already been described with reference to FIG. 1, they will be omitted in the following description, and “steps” described as steps 7 and 8 in FIG. The process for correcting the tone will be described.

  In the second embodiment, a “predetermined value” that is a criterion for the determination in step 7 is registered in advance as the first gradation difference. For example, if 80% is registered as the predetermined value (first gradation difference) and the gradation difference obtained in step 6 is not smaller than 80% (that is, larger), the gradation is changed. The multi-tone character created in step 1 is displayed as it is without correction, and when the tone difference is less than 80%, all the tones are removed and the display is performed using only the character font. Of course, another predetermined value 70% may be selected instead of the predetermined value 80%.

  With reference to FIGS. 9A and 9B, the multi-tone display method of the second embodiment will be described in more detail. FIG. 9A shows the situation of multi-gradation characters stored in a predetermined space by Step 3 of FIG. 8, and is the same as that shown in FIG. If the gradation difference 350 in this case is 75% and the predetermined value registered in advance is 80%, all gradations are removed (step 8).

  FIG. 9B shows the display state at this time. In this case, as a result, multi-tone characters are no longer displayed, and only normal character fonts are displayed. This process is simple and effective for the purpose of improving visibility, and is effective when the display screen is originally small, for example, when the display screen is small. The process in this case is the same as the case shown in FIG. 6 as a result.

  FIG. 10 shows an example of a display device that can realize the display method according to the second embodiment. The display device of Embodiment 1 shown in FIG. 3 has basically the same configuration, but the display device shown in FIG. 10 omits the corrected multi-gradation character generation unit 105 shown in FIG. It has a simpler configuration. That is, in FIG. 3, the corrected multi-gradation character generation unit 105 is a display device based on the premise that multi-gradation characters are corrected. For example, it is only necessary to display a character that is not corrected, that is, a character to which no gradation is added from the OSD generation unit 101, and therefore the expected operation can be performed by providing the switching unit 104. .

  The operation of the multi-tone display device shown in FIG. 10 will be briefly described below.

  Character data determined to be displayed in a predetermined display area supplied from the OSD generation unit 101 is temporarily stored in the buffer memory 102. The character gradation generation unit 103 adds one or more gradations to the character data from the OSD generation unit 101 to create a multi-gradation character. The gradation difference measurement unit 104 measures the gradation difference of the multi-gradation character generated by the character gradation generation unit 103. Although detailed description is omitted here, “measuring the tone difference of multi-tone characters” means measuring the tone difference 350 shown in FIG. 5A as described with reference to FIG. Is meant to do.

  When the gradation difference obtained as a result of the measurement is smaller than a predetermined value, for example, 75%, the switching unit 106 displays a character stored in the buffer memory 102 to which the gradation is not given, such as an LCD. To display. When the gradation difference is larger than a predetermined value, the multi-gradation character from the character gradation generation unit 103 is displayed on the LCD.

  Although not particularly illustrated, the character font portion of the multi-tone character is determined so that the character is easy to read with respect to the background portion of the character. For example, when displaying a multi-tone character on a dark background portion or a black background portion, the character font portion is preferably white. When the background portion is white or bright, the character font portion is preferably a dark color, for example, black. In this case, the entire area for displaying characters may be dark or light, corresponding to the color of the character font.

  As described above, when the luminance difference of the character font portion is increased with respect to the background portion of the character, it is needless to say that the visibility of the character is good. Visibility is extremely effective when displaying characters with a small difference in brightness between the color of the character font part (character color) and the background color of the character (background color). There is an effect that it is possible to suppress deterioration of the material. That is, according to the invention of the present application, even if the character spacing is narrowed in an image where the brightness difference between the character color and the background color cannot be made large due to the necessity of the screen configuration, the visibility of the character is deteriorated. It can be effectively suppressed.

  The multi-tone character display method described above assumes a state in which a plurality of multi-tone characters are arranged. However, even when one character is displayed, the multi-tone character of the present invention is displayed. The display method can be applied effectively. For example, when one multi-gradation character that can be displayed with sufficient visibility on a large-screen television receiver display with a large number of pixels is displayed on the television receiver display with a small pixel number, , The “line segments” constituting the characters may approach each other, resulting in a display with poor visibility. Even in such a case, if the display method of the present invention is applied, it is possible to display multi-gradation characters with reduced deterioration of visibility without changing the display control program.

In addition, as described above, for example, in a television receiver, when performing PIP (picture-in-picture) display in which other channels are displayed on a sub-screen, a small screen without breaking the design of the sub-screen. If a predetermined character string is to be displayed inside, the displayed character itself becomes small, and the same phenomenon as described above occurs.
<Application to TV receivers>
FIG. 11 is a diagram for explaining a case where the multi-tone character display device of the present invention is applied to an actual television receiver. First, an outline of the television receiver in FIG. 11 will be described.

  In FIG. 11, reference numeral 10 denotes an entire television receiver having the liquid crystal display device 22 having a screen size of 16: 9 (1920 × 1010 dots), for example. In the television receiver 10 shown in FIG. 11, the OSD data generated by the OSD generation unit is displayed by the liquid crystal display device 22. The television receiver 10 includes a CPU 6 and a memory 7 connected to the bus 8, and the operation of the television receiver 10 is controlled by various control programs stored in the CPU 6 and the memory 7. .

  That is, the television receiver shown in FIG. 11 is controlled by a computer system including a CPU 6, and a program for operating the television receiver by the computer system is stored in the memory 7. It is obvious that the screen size is not limited to a liquid crystal display device with an aspect ratio of 16: 9.

  The memory 7 is usually composed of a RAM, but may include a ROM in part. Further, a rewritable flash memory or the like may be included. The memory 7 stores an OS for operating the CPU, various control software, and the like. Data relating to program information such as EPG data received via broadcast waves, and OSD necessary for OSD display Image data and the like are stored. The memory 7 has a work area that functions as a work memory necessary for various control operations.

  The television receiver 10 is provided with an analog tuner unit 12 in addition to the digital tuner unit 14 so that an analog broadcast can be received. The external input unit 31 can be connected to various external devices 30 such as a solid-state memory such as an HDD and an SD card, and a disk device such as a BD (Blu-ray disc), DVD, and CD. A BD / DVD / CD recording / reproducing unit 32 is also built in the main body of the apparatus 10. Further, an IP broadcast tuner unit 23 is provided, and IP broadcast reception is also possible.

  In addition, the television receiver 10 includes an AV switch unit 13, a digital demodulation unit 15, a separation unit (DMUX) 16, a video decode / capture unit 17, a video selector unit 18, a video processing unit 19, an addition circuit 20, and a display control unit. 21, liquid crystal display device 22, EPG / OSD / reservation processing unit 24, audio decoding unit 25, audio selector unit 26, audio output conversion unit 27, speaker 28, channel selection unit 33, communication control unit 34, and remote control light receiving unit 35 doing. The television receiver 10 is further provided with an OPC (light) sensor 38 for detecting ambient brightness.

  The “EPG / OSD / reservation processing unit 24” provided in the television receiver 10 has the function of the portion described as the “OSD generation unit 101” in FIGS. 3 and 10 of the present invention.

  The analog tuner unit 12 selects an analog television broadcast signal received through the antenna 11 for receiving an analog broadcast, and performs channel selection according to a channel selection instruction from the channel selection unit 33. The received signal from the analog tuner unit 12 is separated into an audio signal and a video signal in the AV switch unit 13, the video signal is input to the video selector unit 18, and the audio signal is input to the audio selector unit 26.

  The digital tuner unit 14 selects a digital television broadcast signal received via the digital broadcast receiving antenna 40, and selects a channel to be received according to a channel selection instruction from the channel selection unit 33. The received signal from the digital tuner unit 14 is demodulated by the digital demodulation unit 15 and sent to the separation unit (DMUX) 16.

  The IP broadcast tuner unit 23 selects an IP broadcast received via a communication control unit 34 connected to a telephone line / LAN or the like, and receives a specific IP received in response to a channel selection instruction from the channel selection unit 33. The broadcast is selected and the output is sent to the separation unit (DMUX) 16.

  The separation unit (DMUX) 16 separates the multiplexed video data and audio data input from the digital demodulation unit 15 or the IP broadcast tuner unit 23, sends the video data to the video decoding / capture unit 17, and the audio data Is sent to the audio decoding unit 25. Further, the separation unit (DMUX) 16 extracts data such as EPG data included in the broadcast signal and sends it to the EPG / OSD / reservation processing unit 24. The broadcast wave signal extracted by the separation unit (DMUX) 16 is recorded in the memory 7 by writing control by the CPU 6 as necessary.

  The video decoding / capture unit 17 decodes the video data separated by the separation unit (DMUX) 16 and captures video information included in the video data as a still image. The video signal decoded by the video decoding / capture unit 17 is sent to the video selector unit 18. As described above, the video signal from the analog tuner unit 12 is input to the video selector unit 18, and the video signal from the external input unit 31 is also input. The video selector unit 18 selects and outputs one video signal from these input video signals according to the control signal from the CPU 6, and sends it to the video processing unit 19.

  The video processing unit 19 performs video processing such as noise reduction processing, sharpness adjustment, and contrast adjustment on the input video signal so as to obtain an optimal video signal for the liquid crystal display device 22. Convert video data to.

  The display control unit 21 includes a drive circuit for displaying the received video data on the liquid crystal display device 22, and an electronic program table (from the EPG / OSD / reservation processing unit 24) added by the addition circuit 20 ( Electronic program guide (EPG) data or OSD (on-screen display) data is sent to the liquid crystal display device 22 in addition to the video data from the video processing unit 19. The liquid crystal display device 22 displays the transmitted video data on the screen.

  The audio decoding unit 25 decodes the audio data separated by the separation unit (DMUX) 16. The audio decoding unit 25 sends the decoded audio signal to the audio selector unit 26.

  The audio selector unit 26 receives the audio signal from the AV switch unit 13, the audio signal from the external input unit 31, and the audio signal from the audio decoding unit 25, and is selected by the video selector unit 18 under the control of the CPU 6. An audio signal corresponding to the video signal is selected, and the audio signal is sent to the speaker 28 via the audio output conversion unit 27. The audio output conversion unit 27 converts the received audio signal into a signal optimal for reproduction on the speaker 28 and supplies the converted signal to the speaker 28.

  The remote controller light receiving unit 35 is for receiving an optical signal from a remote controller 36 (hereinafter referred to as a remote controller 36) and receiving a control signal from the remote controller 36. The communication control unit 34 performs control so as to establish communication via a network such as a telephone line, a LAN, and the Internet.

  The EPG / OSD / reservation processing unit 24 creates an electronic program guide based on EPG data periodically updated and stored, and draws OSD data stored in the memory 7 in advance. The OSD data is data for drawing various information such as a setting menu screen, a volume cage, a current time, a channel selection, and the like stored in advance in the memory 7, for example. Further, the EPG / OSD / reservation processing unit 24 performs program reservation processing using the electronic program guide.

  As already described, the OSD data raised here includes data whose length changes when, for example, English data is changed to German. Therefore, as already explained, the multi-tone character display method of the present invention has the same hardware configuration, and can be displayed in a multi-lingual television receiver or the like that enables multilingual display by software (program). Therefore, the present invention can be applied very effectively when the OSD data is stored in a predetermined space and expressed in multi-tone characters.

  In the above description, the television receiver is particularly described as an example. However, in addition to this, the television is received by a portable device capable of viewing the television, for example, a mobile phone, a car navigation system, a portable game terminal, or the like. Obviously, the display method according to the invention of the present application can also be applied. Further, it is clear that the present invention can be effectively applied to all devices that display multi-gradation characters corresponding to multiple languages, even if the display device does not have a function for receiving television. .

<Program, storage medium>
Each block of the multi-grayscale character display device shown in FIGS. 3 and 10 may be realized by hardware by a logic circuit formed on an integrated circuit (IC chip), or may be a CPU (Central Processing Unit). ) May be implemented in software. The CPU may be provided as a dedicated CPU for performing the display method of the present application in the display of the present application. However, when applied to a television receiver or the like, the CPU provided in the television receiver may also be used. good.

  When implemented in software, a multi-tone character display device includes a CPU that executes instructions of a program that realizes each function, a ROM (Read Only Memory) that stores the program, and a RAM (Random that expands the program). Access Memory), a storage device (recording medium) such as a memory for storing the program and various data, and the like. The object of the present invention is to record a program code (execution format program, intermediate code program, source program) of a control program for a multi-tone character display device, which is software for realizing the above-described functions, in a computer-readable manner. This can also be achieved by supplying the recording medium to a display device for multi-gradation characters and reading and executing the program code recorded on the recording medium by the computer (or CPU or MPU).

  Examples of the recording medium include tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and disks including optical disks such as CD-ROM / MO / MD / DVD / CD-R. IC cards (including memory cards) / optical cards, semiconductor memories such as mask ROM / EPROM / EEPROM / flash ROM, PLD (Programmable logic device), FPGA (Field Programmable Gate Array), etc. Logic circuits can be used.

  The program code may be supplied via a communication network. The communication network is not particularly limited as long as it can transmit the program code. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication network, and the like can be used. The transmission medium constituting the communication network may be any medium that can transmit the program code, and is not limited to a specific configuration or type. For example, even with wired lines such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, and ADSL (Asymmetric Digital Subscriber Line) line, infrared rays such as IrDA and remote control, Bluetooth (registered trademark), IEEE 802.11 wireless, HDR ( It can also be used by radio such as High Data Rate (NFC), Near Field Communication (NFC), Digital Living Network Alliance (DLNA), mobile phone network, satellite line, and digital terrestrial network.

  It should be understood that the embodiments disclosed above are illustrative and non-restrictive in every respect. The scope of the present invention is shown not only by the above description but also by the scope of claims for patent, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims for patent.

  The present invention provides a display of multi-gradation characters capable of displaying high-quality multi-gradation characters on all display panels such as LCDs and ELs used in various information devices typified by television receivers. The present invention relates to a method and a display device and has high industrial applicability.

101 OSD generation unit 102 buffer memory 103 character gradation generation unit 104 gradation difference measurement unit 105 corrected multi-gradation character generation unit (character gradation correction unit)
DESCRIPTION OF SYMBOLS 106 Switching part 107 Liquid crystal display device 200 The character font part of a multi-tone character 201 The gradation 1 part of a multi-tone character 202 The gradation 2 part of a multi-tone character 203 The background part 210 The character font part of a multi-tone character Gradation (brightness level)
211 Gradation (brightness level) in the gradation 1 part of multi-gradation characters
212 Gradation (brightness level) in the gradation 2 part of a multi-gradation character
213 Background gradation (brightness level)
300, 310 Multi-tone character font portion 301, 311 Multi-tone character tone 1 portion 302, 312 Multi-tone character tone 2 portion 303, 313 Multi-tone character tone 3 portion 304 background portion 305 character font 310, gradation 1 portion 311, gradation 2 portion 312, gradation 3 portion 313 multi-gradation character 315 character font 300, gradation 1 portion 301, gradation 2 Multi-tone character 350 having a portion 302 and a portion 3 of gradation 3 A gradation difference (brightness level difference) between a character font portion and a portion of gradation 3

Claims (14)

A method for displaying multi-gradation characters by adding one or more gradations to a peripheral portion of a character font adjacent to a character font so that input character data can be displayed as multi-gradation characters,
By adding one or more tone to the peripheral portion of the character font of the input character data, and the multi-gradation character generating step of generating a multi-tone characters,
The gradation of character font parts of the multi-gradation characters, and gray-scale difference measurement step of measuring a gradation difference between the gradation in the intermediate portion between the character font of adjacent multi-tone characters,
Correcting the gradation of the multi-gradation character to create a corrected multi-gradation character when the gradation difference obtained in the step of measuring the gradation difference is less than a predetermined gradation difference ; With
When the gradation difference obtained in the step of measuring the gradation difference is less than the predetermined gradation difference, the corrected multi-gradation character is replaced with the output of the character with no gradation added. A multi-tone character display method, wherein: One width of the gradation added to the peripheral part of the character font is a predetermined width, and the gradation difference measuring step is based on the step of measuring the character interval between adjacent characters and the character interval. The multi-tone character display method according to claim 1, further comprising a step of converting to a tone difference. The step of creating the corrected multi-tone character includes
The step of removing all the added gradations when the gradation difference measured in the gradation difference measurement step is smaller than a predetermined first gradation difference. Item 3. The multi-tone character display method according to Item 1 or 2. The step of creating the corrected multi-tone character includes
If the gradation difference measured in the gradation difference measurement step is less than or equal to a predetermined first gradation difference, removing all of the added gradations;
A second gradation difference measured in the gradation difference measurement step is greater than the first gradation difference, and is a predetermined gradation difference that is greater than the first gradation difference. If the gradation difference is smaller than the second gradation difference, the method includes a step of removing the added gradation from a portion farthest from the character font until the second gradation difference is greater than or equal to the second gradation difference. The multi-tone character display method according to claim 1, wherein multi-tone characters having a gradation difference equal to or higher than a tone difference are output. The one or more gradations added to the peripheral portion of the character font by the multi-gradation character creation step are gradations obtained by equally dividing the difference between the gradation of the character font and the gradation of the background portion of the character. display method of multi-tone characters according to any one of claims 1 to 4, characterized in that it. 1 or more tone to be added to the peripheral portion of the character font of the input character data is to reduce the change in tone on the side close to the character font, the gradation on the side closer to the background portion of the character change display method of multi-tone characters claimed in any one of 4, characterized in that in which was increased. The multitone character display method according to any one of claims 1 to 6 , wherein a character font of the multitone character is white and a background portion of the character is black. The multitone character display method according to any one of claims 1 to 6 , wherein a character font of the multitone character is black and a background portion of the character is white. Includes a character gradation generating unit by adding one or more tone the peripheral portion of the character font generating multi-gradation character, the multi-input character data, obtained by adding one or more tone the peripheral portion of the character font A character display device capable of displaying as gradation characters,
A gradation difference measuring unit for measuring a gradation difference between a gradation of a character font of a multi-gradation character and a gradation in an intermediate portion between adjacent character fonts of a multi-gradation character;
When the measurement result of the gradation difference measuring unit is greater than or tone difference to a predetermined multilingual one or more tone from the character gradation generating unit instead of the character output gradation is not added is granted A display device for multi-gradation characters, comprising a switching unit for outputting gradation characters. A character gradation generation unit for adding one or more gradations to the peripheral part of the character font is provided, and the input character data can be displayed as a multi-gradation character with one or more gradations added to the peripheral part of the character font. A character display device,
A gradation difference measuring unit for measuring a gradation difference between a gradation of a character font of a multi-gradation character and a gradation in an intermediate portion between adjacent character fonts of the multi-gradation character;
The gradation of the multi-gradation characters generated by the character gradation generating unit by correcting, with a correction multi-tone character generator for creating a corrected multi-gradation characters,
When the measurement result of the gradation difference measurement unit is less than a predetermined gradation difference, the character output without gradation added and the corrected multi-gradation character can be switched and output. Multi-tone character display device. Television receiver including the display device of the multi-gradation characters of claim 9 or 10. Mobile apparatus including the display device of the multi-gradation characters of claim 9 or 10. A program for causing a computer to operate as the multi-tone character display device according to claim 9 or 10 , wherein the computer functions as each unit included in the multi-tone character display device. A computer-readable recording medium on which the program according to claim 13 is recorded.